Rear wiper issue

[Drewk1]

Just sorting out Vera ready for the new season and I decided to finally look at the non working rear wiper.
I know its not particularly good but its fitted and I would like it working.
I've fitted a new motor and it now works but doesn't stop!
It starts when the ignition is switched on and pushing the stalk control operates the rear washer but doesn't stop/start it. .
I've swapped relay 72 for another one but it still doesn't stop.
I guess the stalk control is next for investigation but does anyone have suggestions on what's up?

1990 Autosleeper Trident 1.9 petrol
 

[Mocki]

You should clean the stalk contacts , switching it off involves pushing it towards the steering wheel , not up or down iirc

[Drewk1]

I'm stumped now.

Brand new motor.
Brand new switch
tried 3 x relays

And still motor will not stop.
It still runs with relay removed so now wondering if the wiring has been altered?

Any ideas anyone

[Robsey]

If the motor now runs, there can only be a few issues.
and I assume all are due to wiring.

1 - motor wired up wrong
2 - park position switch not working.
3 - wiring shorted to a live feed somewhere.
(especially if the wiper continues to run with the relay out).
Does it run with the fuse out?

it could be a matter of getting your volt meter out, and testing the wire all the way from the fusebox, the stalk switch, the relay, the loom to the hatch, and the loom to the motor.

[Robsey]

looking at the motor...
there is a direct feed to the park position switch of the wiper motor.
This is a black / grey wire and is linked to fuse 12
Fusebox Plug E pin 8 (E8)

The X-relief (ignition live when not cranking) live feed is the other wire.
green / black from the relay.
Fusebox Plug E pin 2 (E2).

I have two guesses -
either the green / black and the black / grey wires want swapping...

or the park switch within the motor is faulty - stuck in the on position.

So - ideally see which wires are live...
with the relay plugged in,
and unplugged.

only the green / black wire should be affected by the relay being removed, refitted and energised by the stalk switch.

the black grey will be live all the time the ignition is on (engine not cranking).
the X relay (relief circuit) is operating.

[Drewk1]

Thanks Robsey 
It doesn't run with the fuse out.
I'll get my meter out and do some testing.

[Robsey]

One other test you could do is for the operation of the park position switch.
Put a tester across the terminals for the brown wire and the black/grey wire.
Set the meter to measure resistance.
Run the wiper and see if the switch opens and closes.

If this stays always closed (resistance of the motor windings) then that circuit is not switching off.

Do the same between the green / black and brown wire terminals.

If the resistance value changes, open circuit and motor windings resistance (closed), then the wires are the wrong way round.

If the resistance continuously shows a value for the motor windings, then we can assume the park position switch is defective.

This does sound back to front, but it is the logical way to verify where the park position switch is, and whether it is working.

--------------------------------------

The only other thought that comes to mind, is the wires in the rubber hose between the van body and the tail-gate.

With constant flexing and age the wires can either snap cutting power to the motor,
Or the insulation can crack allowing the inner wire cores to short together.

Here is a similar situation on one of my cars back in early 2019...



And my other car in 2018...

[Drewk1]

Thanks again I really appreciate it.
 

[Robsey]

As before, my pleasure.
That is what these forums are for.
Sharing experience and information / ideas between like-minded people.

As you can see, I run older cars...
(Not a fan of modern plastic euro-boxes full of micro-electronics).

My youngest car is 18 years old at the end of the month. (First photo above).
The other car is 29 years old this August. (Second photo above).
And the part-built van hitting 40 years old in April.
Thankfully, it has no electrics in the tail-gate.

[Drewk1]

I'm happy to report following some testing the wires to the motor were indeed reversed.
Someone had put connectors in before the motor connector which had swapped the wires.
A quick snip and new connectors fitted the correct way around and she works and stops !!!

Just need to set up 8° position of the lever now.

Hopefully this thread will help someone in the future with the same issue.
 

[Robsey]

Glad to hear you got it sorted.
Now for the next challenge.

Happy motoring !!